Rotor structure for rotary regenerative heat exchanger



J- CONDE Nov. 3, 1964 ROTOR STRUCTURE FOR ROTARY REGENERATIVE HEATEXCHANGER Filed May 28 1962 2 Sheets-Sheet 1 INVENTOR. Jame; Co/roe Nov.3, 1964 J. CONDE 3,155,152

ROTOR STRUCTURE FOR ROTARY REGENERATIVE HEAT EXCHANGER Filed May 28,1962 2 Sheets-Sheet 2 INVENTOR. Y 9/77e5 Cone e B United States Patent3,155,152 ROTOR STRUCTURE FOR RQTARY REGENERA- TI'VE HEAT EXCHANGERJames ond, Wellsviile, N.Y., assignor to Combustion Engineering, Inc,New York, N.Y., a corporation of Delaware Filed May 28, 1962, Ser. No.198,161 9 Claims. (Cl. 165-7) This invention relates to heat exchangeapparatus of the rotary regenerative type that is adapted tocontinuously transfer heat from a stream of heating fluid to anindependent fluid to be heated. More particularly, this inventionrelates to heat exchange apparatus that is not adversely affected bythermal deformation of its relatively rotating parts.

In rotary regenerative heat exchange apparatus of the type referred to,a cylindrical rotor carrying compartment of heat absorbent material isfirst exposed to a flow of heating fluid such as hot exhaust gas that isdirected through a limited portion of the rotor. Upon rotating the rotorabout its axis, the heated heat absorbent material is positioned in thepath of a relatively cool fluid to be heated such as air whereby theheat of the gas may be transferred thereto. The rotor is surrounded by ahousing formed with openings at spaced ends that simultaneously directthe heating fluid and the fluid to be heated through spaced compartmentsof the rotor.

Heat exchange apparatus of this type is eflicient and is widely used forapplications operating at modest temperature levels that may range, forexample, up to 1000 F. For temperatures that exceed this approximatelimit, however thermal distortion of the rotor and rotor housing becomesexcessive and it becomes increasingly diflicult if not impossible tomaintain any semblance of a sealing relationship between the relativelyrotatable parts of the apparatus. Furthermore, heat from the rotor isconducted through its support structure to its support and guidehearings to the extent that bearing life is substantially reduced andmaintenance costs are correspondingly increased.

This invention is therefore directed to a novel rotor arrangement thatprecludes excessive thermal deformation of the rotor throughout wideranges of temperature variation. The invention further provides a novelrotor arrangement that isolates bearing structure at spaced ends of therotor from the deleterious eifects of excessive heat.

These and other objects of this invention will be better understood uponconsideration of the following detailed description of an illustrativeembodiment thereof when read in conjunction with the following drawingsin which:

FIGURE 1 is a sectional elevation of the heat exchanger made inaccordance with the invention.

FIGURE 2 is a plan view on line 22 of FIGURE 1.

FIGURE 3 is a perspective view of the post shell and its means ofsupport.

As will be apparent from the figures of the drawing, the arrangementshown relates generally to a rotary regenerative heat exchanger of theLjungstrom type having a rotor divided into sector-shaped compartmentsby radial partitions in order that a mass of heat absorbent material maybe suitably housed therein. The rotor is surrounded by a rotor housinghaving inlet and outlet openings at opposite ends thereof for thecounter-current flow of a heating fluid and a fluid to be heated. Theinlet for the heating fluid is at the lower end of the rotor while theinlet for the cooler fluid to be heated is at its upper end to thusposition the hot end of the rotor at the bottom while the cold end liesat the top end of a vertical rotor shaft. It will be apparent that thecold or upper end of the rotor will be subjected to less thermaldistortion than the 3,155,152 Patented Nov. 3, 1964 bottom or hot end ofthe rotor that lies in the zone of maximum temperature variation.

According to the invention a rotor shaft It is supported at its upper orcold end by a support bearing 12 mounted on an independent support beam14. Similarly a guide bearing 16 carried by a secondary beam 18 issuspended by rods 22 from the support beam 14 at the cold end of theheat exchanger.

A post shell 24 concentrically surrounds the rotor shaft at its upperend or cold end in spaced relationship and is secured thereto by aseries of tangential support ribs 26 that are adapted to flex laterallyto compensate for a growth in diameter of the post shell 24. A series ofradial partitions or diaphragms 23 extend radially outward from the postshell 24 to a concentric rotor shell 32 to provide a series of sectorialcompartments 34 that are each adapted to carry a mass of heat absorbentmaterial through which the heating fluid and the fluid to be heated arealternately directed as the rotor is rotated about its axis by any of avariety of motive arrangements not here illustrated.

The fixed radial partitions 23 are positioned only at the cold end ofthe rotor between the post shell and rotor shell. Dependent partitions33 are pivotally linked at 35 to the fixed partitions, and sized toextend axially through the cold end of the rotor in radial alignmentwith the fixed load carrying partitions 28. The dependent partitions 33loosely abut the inner surface of the rotor shell at their outermostends while their radially inner ends similarly abut a cylindrical jacket36 that is supported by flange 37 and comprises a continuation for thepost shell 24 that is arranged to provide a space 38 through which airmay flow. Axially disposed channel members 42 are paired in radialalignment on the cylindrical jacket 36 and the rotor shell 32 to provideholding slots for the end edges of the dependent partitions 33 topreclude their lateral displacement due to pressure differences inadjacent rotor compartments. The channel members 42 thus provide a basicsealing function that cooperates With inter-partition seals 44 andradial seals 46 to limit fluid leakage between adjacent rotorcompartments. Circumferential seals 48 around the end edges of the rotorconfront imperforate portions of the adjacent housing structure topreclude fluid by-passing the rotor and flowing through the annularspace between the rotor shell and the rotor housing.

The housing 52 that surrounds the rotor includes inlet and outlet ducts54 and 56 for a heating fluid and spaced ducts 5S and 62 for the fluidto be heated. The cold end ducts 56 and 58 are suspended by means 64directly from the main beam 14, while the hot end ducts 54 and 62 arecarried by supports 66 which are in turn suspended from the main supportbeam 14 by rods 22 and secondary beam 18.

To further isolate the rotor shaft from the heat of the rotor, thecylindrical surface of the post shell and the aligned cylindrical jacketare provided with a layer of thermal insulating material 68, the innersurface of which comprises the surface of a cooling duct that surroundsthe rotor shaft it whereby a flow of cooling air induced by naturalcirculation may course through the duct and carry away heat which maypass through the insulation material 68.

By the arrangement of this invention, high temperature which couldadversely atfect the rotor shaft, support beams and support bearing, aresubstantially isolated therefrom. Moreover, the rotor is attached to therotor shaft only at its cold end where thermal distortion that doesoccur is at a minimum and where a unique arrangement of support ribspermits slight variations in their shape to compensate for any thermaldeformation of rotor structure connected thereto.

While this invention has thus been described with refer- I once to theembodiment illustrated in the drawing, it is evident that variouschanges may be made without departing from the spirit of the inventionand it is intended that all matter contained in the above description orshown in the accompanying drawings shall be interpreted as illustrativeand not in a limiting sense.

I claim:

1. Rotary regenerative heat exchange apparatus having a rotor includinga cylindrical shell joined to a rotor post by radial partitions toprovide a series of sectorshaped compartments that carry a mass of heatexchange material, a housing surrounding the rotor provided at oppositeends with inlet and outlet ports for a heating fluid and fluid to beheated, said rotor post comprising a central support shaft and a shaftshell extending concentrically between the rotor shell and rotor shaft,and a plurality of support ribs extending tangentially from the supportshaft to the post shell arranged to permit lateral flexing of the ribsto compensate for radial expansion of the post shell.

2. Rotary regenerative heat exchange apparatus comprising a rotor havinga cylindrical shell joined to a rotor post by radial partitions toprovide a series of sectorshaped compartments that carry a mass of heatexchange material, a housing surrounding the rotor provided at op positeends with inlet and outlet ports for a heating fluid and a fluid to beheated, said rotor post comprising a central support shaft and a shaftshell extending concentrically between the rotor shell and rotor shaft,and a plurality of support ribs extending tangentially from the supportshaft to be post shell at the end of the rotor adjacent the inlet forthe fluid to be heated arranged to provide support means that flexlaterally to provide a continuous support that compensates for radialexpansion of the post shell.

3. Rotary regenerative heat exchange apparatus having a rotor includinga cylindrical rotor shell joined to a rotor post by fixed radialpartitions to provide a series of fixed sector-shaped compartments thatcarry a mass of heat exchange material, a housing surrounding the rotorprovided at opposite ends with inlet and outlet ports for a heatingfluid and a fluid to be heated, said rotor post comprising a centralsupport shaft and a shaft shell extending concentrically between therotor shell and rotor shaft a distance less than the length of saidcentral shaft, and a plurality of support ribs extending tangentiallyfrom the support shaft to the post shell arranged to provide a series ofrotor supports that flex laterally to compensate for radial expansion ofthe post shell.

4. Heat exchange apparatus as defined in claim 3 wherein the shaft shelllies at the end of the rotor adjacent the inlet for the fluid to beheated.

5. Heat exchange apparatus as defined in claim 3 4 wherein the shaftshell extends axially a distance less than one-half the length of therotor shell.

6. Heat exchange apparatus as defined in claim 3 having a dependentpartition suspended from each radial partition and a cylindrical jacketsuspended from said shaft shell arranged to provide movable walls forthe ends of said compartments that lie adjacent to the inlet ports forthe heating fluid.

7. Rotary regenerative heat exchange apparatus having a rotor includinga rotor shell, a central rotor shaft, a shaft shell extendingconcentrically between the rotor shell and rotor shaft a distancesubstantially less than the length of said rotor shell, a plurality ofsupport ribs extending tangentially from the rotor shaft to the shaftshell, a series of partitions extending radially between the shaft shelland rotor shell to provide a series of sector-shaped compartmentstherebetween, said partitions being divided axially to provide fixedsupport partitions and dependent partitions subjacent thereto, saidsupport partitions being fixedly secured at radially opposite ends tothe shaft shell and rotor shell while the dependent partitions arepivotally linked to the support partitions and arranged to slidably abutthe rotor shell on their outboard ends to permit relative movementtherebetween.

8. Rotary regenerative heat exchange apparatus having a rotor includinga cylindrical rotor shell, a central rotor shaft, a shaft shellextending concentrically between the rotor shell and rotor shaft adistance substantially less than the length of said rotor shell, aplurality of support ribs extending tangentially from the rotor shaft tothe post shell, a cylindrical jacket in axial alignment with the postshell and supported thereby, a series of partitions extending radiallybetween the shaft shell and the rotor shell to provide a series ofsectorial compartments therebetween, said partitions being axiallydivided to provide a support partition and a dependent partitionsubjace'nt thereto, said support partition being fixedly secured atradially opposite ends to the shaft shell and the rotor shell while thedependent partition is pivotally carried by the support partition and isadapted to slidably abut the rotor shell and the cylindrical jacket atits radial ends to permit relative movement therebetween.

9. Rotary regenerative heat exchange apparatus as defined in claim 8including an annular layer of thermal insulating material arranged toabut the surface of the shaft shell and the cylindrical duct to precludethe conduction of heat from the compartments of the rotor to the centralrotor shaft.

Hennig May 6, 1947 Theoclitus Apr. 23, 1957

8. ROTARY REGENERATIVE HEAT EXCHANGE APPARATUS HAVING A ROTOR INCLUDINGA CYLINDRICAL ROTOR SHELL, A CENTRAL ROTOR SHAFT, A SHAFT SHELLEXTENDING CONCENTRICALLY BETWEEN THE ROTOR SHELL AND ROTOR SHAFT ADISTANCE SUBSTANTIALLY LESS THAN THE LENGTH OF SAID ROTOR SHELL, APLURALITY OF SUPPORT RIBS EXTENDING TANGENTIALLY FROM THE ROTOR SHAFT TOTHE POST SHELL, A CYLINDRICAL JACKET IN AXIAL ALIGNMENT WITH THE POSTSHELL AND SUPPORTED THEREBY, A SERIES OF PARTITIONS EXTENDING RADIALLYBETWEEN THE SHAFT SHELL AND THE ROTOR SHELL TO PROVIDE A SERIES OFSECTORIAL COMPARTMENTS THEREBETWEEN, SAID PARTITIONS BEING AXIALLYDIVIDED TO PROVIDE A SUPPORT PARTITION AND A DEPENDENT PARTITIONSUBJACENT THERETO, SAID SUPPORT PARTITION BEING FIXEDLY SECURED ATRADIALLY OPPOSITE ENDS TO THE SHAFT SHELL AND THE ROTOR SHELL WHILE THEDEPENDENT PARTITION IS PIVOTALLY CARRIED BY THE SUPPORT PARTITION AND ISADAPTED TO SLIDABLY ABUT THE ROTOR SHELL AND THE CYLINDRICAL JACKET ATITS RADIAL ENDS TO PERMIT RELATIVE MOVEMENT THEREBETWEEN.